1. Field of the Invention
The present invention relates to a centrifugal type clutch brake device, and more specifically to a novel, improved centrifugal type clutch brake device having a substantially more simplified structure in which a moving means consisting of a screw, pin or the like is provided between a centrifugal clutch housing and a ring-like drive disc of a centrifugal clutch and in which, after the centrifugal clutch is disengaged, the ring-like drive disc is moved axially upwards to effect braking.
2. Description of the Related Art
FIGS. 6 and 7 schematically show how a conventionally used clutch brake device of the type described above is formed according to an existing technique, with the titles of the relevant documents not being disclosed.
In FIGS. 6 and 7, numeral 1 indicates a rotation shaft provided on the side of a driving means 2, such as an engine, and on the upper portion of the rotation shaft 1, there is provided an actuator plate 4 through the intermediation of a first bearing 3 so as to be rotatable by means of an operation system cable 5. On the back side of this actuator plate 4, there is provided an actuator 9 mounted to a plate 6 on the driving means 2 side through the intermediation of a column 7 and a set spring 8 so as to be vertically movable (In FIG. 6, it is shown in the raised and lowered states, respectively, on the right-hand side and the left-hand side with respect to the center line of the drawing).
Between recesses 4a and 9a of the actuator plate 4 and the actuator 9, there is provided a ball 10 with a retainer.
Fixed to the middle position of the rotation shaft 1 is a drive disc 11 substantially in the form of a disc, and the lower portion of this drive disc 11 is equipped with a blade holder 13 through the intermediation of a second bearing 12, with the blade holder 13 being connected to a driven member, such as a blade (not shown).
Arranged inside the blade holder 13 is a facing plate 16 urged by a clutch spring 14 and having a facing 15, with the lower surface of the drive disc 11 and the lower surface of the actuator 9 being capable of coming into contact with and moving away from the facing 15.
Next, the operation of this device will be described. The left-hand side portion of the device in FIG. 6 is connected to the operation cable 5. In the state in which the brake is disengaged and the clutch is engaged, the blade (not shown) connected to the blade holder 13 rotates with the rotation of the rotation shaft 1, which is driven by the driving means 2.
When, in the above-described state, the operation system cable 5 is restored by a brake spring 5A, the actuator plate 4 rotates, and the ball 10 with a retainer is detached from the recess 9a. The actuator 9 is lowered as shown on the right-hand side of FIG. 6 and comes into contact with the facing 15. At the same time, the contact between the drive disc 11 and the facing 15 is canceled, and the rotation of the rotation shaft 1 is not transmitted to the blade holder 13, with the result that the rotation of the blade holder 13 is stopped.
The conventional clutch brake device, constructed as described above, has the following problem.
That is, to rotate and stop the blade holder, it is necessary to rotate the actuator and vertically move the actuator through the ball, resulting in a rather complicated clutch/brake mechanism. Further, a dedicated cable and an operating lever are indispensable to the operation system, resulting in high cost and necessitating novel designing of the apparatus main body.
As is admitted, a very high level of safety is required of the device. However, since it does not allow post-mounting to a novel/used apparatus, the device has not very much found its way throughout foreign countries, and it is very difficult for the device to meet the recent demand for lower price.